Egg Noodle Lasagna

6 1/2 cups uncooked wide egg noodles
3 tablespoons butter or margarine
1 1/2 pounds ground beef
2 1/4 cup spaghetti sauce
6 ounces processed cheese such as Velveeta, cubed
3 cups shredded mozzarella cheese

Cook noodles according to package directions; drain. Add butter and toss to coat.

In a skillet, cook beef over med heat until no longer pink; drain.

Spread a fourth of the spaghetti sauce in an ungreased 5 quart slow cooker. Layer with a third of the noodles, a third of the beef, a third of the remaining sauce and a third of the cheeses. Repeat layers twice.

Cover and cook on low for 4 hours or until cheese is melted and lasagna is heated through.